Technical Field
The present invention relates to a reinforced brick masonry column with polyester thread reinforcement strips.
Description of the Related Art
The “background” description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as prior art at the time of filing, are neither expressly or impliedly admitted as prior art against the present invention.
A masonry structure is generally defined as an assembly of stones, blocks and/or bricks laid one above the other using a binding material e.g. a cement mortar. These masonry structures are adequately resistant to vertical in-plane loads, yet pose limited resistance to lateral forces caused by earthquakes, tornados, etc. due to low flexural strength and toughness. Several earthquakes in the recent history such as the Great Tohoku Kanto earthquake in March 2011 in Japan, the earthquake in Chile in 2010, and the earthquake in the Northern areas of Pakistan in October 2005 were the deadliest for the people living in masonry structures. These events left a vast trail of destruction and crippled the economies of these countries but in spite of the dangers, people in rural areas continue to rely on masonry because it is economical, durable and does not require a highly skilled labor [Ashraf, M.: “Development of low-cost and efficient retrofitting technique for unreinforced masonry buildings”, Ph.D. Dissertation, University of Engineering & Technology, Peshawar, Pakistan, (2010); Smith, A., and Redman, T.: “A critical review of retrofitting methods for unreinforced masonry structures”, EWB-UK Research Conference, Hosted by The Royal Academy of Engineering, 20 Feb. (2009); Mayorca, P. and Meguro, K.: “Proposal of an efficient technique for retrofitting unreinforced masonry dwellings”, Proceeding of 13th world conference on earthquake engineering Vancouver, B.C, Canada, I: 22-29, Aug. (2004); Javed, M.: “Seismic Risk Assessment of Unreinforced Brick Masonry Systems of Northern Pakistan”, Ph.D. Dissertation, University of Engineering & Technology, Peshawar, Pakistan, (2009); each incorporated herein by reference in its entirety].
In the past several decades, research has been dedicated toward strengthening and rehabilitating masonry structures. New methods have shown to be effective against earthquakes [Ishibashi, T. and Tsukishima, D.: “Seismic damage of and seismic rehabilitation techniques for railway reinforced concrete structures”, Journal of Advanced Concrete Technology, 7(3): 287-296 (2009); Cook, R. A., Doerr, G. T. and Klingner, R. E.: “Bond stress model for design of adhesive anchors”, ACI Structural Journal, 90(5): 514-24 (1993); Cook, R. A., Kunz J., Fuchs W. and Konz, R. C.: “Behavior and design of single adhesive anchors under tensile load in uncracked concrete”, ACI Structural Journal, 95(1): 9-26 (1998); Zamora, N. A., Cook, R. A., Konz, R. C. and Consolazio, G. R.: “Behavior and design of single, headed and unheaded, grouted anchors under tensile load”, ACI Structural Journal, 100(2): 222-30 (2003); Saleem, M. and Tsubaki, T.: “Multi-layer model for pull-out behavior of post-installed anchor”, Proc. FRAMCOS-7, Fracture Mechanics of Concrete Structures, AEDIFICATIO publishers, Germany, II: 823-830 (2010); Saleem, M.: “Cyclic Pull-out Push-in Shear-Lag Model for Post-Installed Anchor Infill Assembly”, Arabian Journal of Science & Technology, Volume 39, Issue 12, pp. 8537-8547, December 2014, Springer, DOI 10.1007/s13369-014-1423-x; Hameed, A., Saleem, M., Qazi, A. U., Saeed, S., Ilyas, M. & Bashir, A.: “Mitigation of Seismic Pounding between Adjacent Buildings”, Pakistan Journal of Science, ISSN: 0030-9877, Vol. 64, No. 4, Pg. 326-333, December, 2012; Hameed, A., Saleem, M., Qazi, A. U., & Rizwana, H.: “Seismic Response Evaluation of Base Isolated Buildings”, Pakistan Journal of Science, ISSN: 0030-9877, Vol. 65, No. 1, Pg. 46-54, March, 2013; each incorporated herein by reference in its entirety]. Many of these techniques employ post-installed anchor bars for the retrofitting process. Among those, the most common techniques for increasing the confinement and performance of structures are fiber reinforced polymer wraps, post tensioning, steel jacketing, ferro-cement jacketing, concrete jacketing, and shortcreting [Ishibashi, T. and Tsukishima, D.: “Seismic damage of and seismic rehabilitation techniques for railway reinforced concrete structures”, Journal of Advanced Concrete Technology, 7(3): 287-296 (2009); Cook, R. A., Kunz J., Fuchs W. and Konz, R. C.: “Behavior and design of single adhesive anchors under tensile load in uncracked concrete”, ACI Structural Journal, 95(1): 9-26 (1998); Zamora, N. A., Cook, R. A., Konz, R. C. and Consolazio, G. R.: “Behavior and design of single, headed and unheaded, grouted anchors under tensile load”, ACI Structural Journal, 100(2): 222-30 (2003); Saleem, M. and Tsubaki, T.: “Multi-layer model for pull-out behavior of post-installed anchor”, Proc. FRAMCOS-7, Fracture Mechanics of Concrete Structures, AEDIFICATIO publishers, Germany, II: 823-830 (2010); Saleem, M.: “Cyclic Pull-out Push-in Shear-Lag Model for Post-Installed Anchor Infill Assembly”, Arabian Journal of Science & Technology, Volume 39, Issue 12, pp. 8537-8547, December 2014, Springer, DOI 10.1007/s13369-014-1423-x; Hameed, A., Saleem, M., Qazi, A. U., Saeed, S., Ilyas, M. & Bashir, A.: “Mitigation of Seismic Pounding between Adjacent Buildings”, Pakistan Journal of Science, ISSN: 0030-9877, Vol. 64, No. 4, Pg. 326-333, December, 2012; Zhuge, Y.: “FRP-Retrofitted URM Walls under in Plane Shear: Review and Assessment of Available Models”, ASCE Journal of Composites for Construction, 14(6): 743-753, (2010); Meguro, K., Mayorca, P., Sathiparan, N., Guragain, R., and Nesheli, N.: “Shaking Table Tests of ¼ Scaled Masonry Models Retrofitted with PP-band Meshes”, Proceedings of the Third International Symposium on New Technologies for Urban Safety of Mega Cities in Asia, Singapore, 1: 9-18, (2005); Coburn, A. and Spence, R.: “Earthquake Protection”, West Sussex: John Wiley & Sons Ltd., ISBN 0-471-49614-6, (2002); Yoshimura, M. and Meguro, K.: “Proposal of Retrofitting Promotion System for Low Earthquake-Resistant Structures in Earthquake Prone Countries”, Proceedings on 13th World Conference on Earthquake Engineering, Vancouver, Canada, 1(927): 221-235, (2004); Navaratnarajah, S.:” Experimental study of PP-band mesh seismic retrofitting for low earthquake masonry resisting structures: PhD Dissertation, Department of Civil Engineering, University of Tokyo, Japan, (2008); Hamid, M. and Ingham, J. S.: “Diagonal Compression Testing of FRP Retrofitted Unreinforced Clay Burnt bricks masonry Wallets”, Journal of Composites for Construction, 15(5): 810-820, (2011); Turco, V., Secondin, S., Morbin, A., Valluzzi, M. R., and Modena, C.: “Flexural and shear strengthening of unreinforced masonry with FRP bars”, Composites Science and Technology, 6(1): 289-296, (2006); Sathiparan, N., Mayorca, P., Nesheli, K. N., Guragain, R. and Meguro, K.: “Experimental study on in-plain and out-of-plain behaviour of Masonry Wallettes retrofitted by PP-Band meshes”, Seisan Kenkyu, 58 (3): 197-213 (2006); Bakhteri, J., Makhtar, A., and Sambasivam, S.: “Finite Element Modeling of Structural Clay Brick Masonry Subjected To Axial Compression”, Jurnal Tecknologi, 41(B): 221-231, (2004); Farooq, S. H., Ilyas, M. and Ghaffar, A.: “Technique for strengthening of masonry wall panels using steel strips”, Asian Journal of Civil Engineering (Building and Housing), 7(6): 972-985, (2006); Macabuag, J.: “Dissemination of Seismic Retrofitting Techniques to Rural Communities”, EWB-UK National Research Conference, I: 13-17, (2010); each incorporated herein by reference in its entirety]. However, these techniques usually require skilled labor, understanding of structural complexities, overcoming issues related to the lack of connectivity of the retrofitting material to the masonry [Yoshimura, M. and Meguro, K.: “Proposal of Retrofitting Promotion System for Low Earthquake-Resistant Structures in Earthquake Prone Countries”, Proceedings on 13th World Conference on Earthquake Engineering, Vancouver, Canada, 1(927): 221-235, (2004); Navaratnarajah, S.:” Experimental study of PP-band mesh seismic retrofitting for low earthquake masonry resisting structures: PhD Dissertation, Department of Civil Engineering, University of Tokyo, Japan, (2008); each incorporated herein by reference in its entirety], and mostly involve large expenses to strengthen the structures. However, little attention in the past has been focused on developing a low-cost practical solution for strengthening unreinforced masonry structures in underprivileged localities.
In view of the forgoing, one objective of the present invention is to provide a reinforced brick masonry column, and a method for reinforcing a masonry structure by effectively mounting and tightening reinforcement strips, which are made of a plurality of polyester threads and a matrix material (e.g. an adhesive), to protect the masonry structure from lateral forces caused by earthquakes and other natural occurring phenomena that generally produce bending moments in the masonry structure. The disclosed method can easily and economically be applied to reinforce masonry structures in underprivileged regions.